There are at least a few runners here, so let me try asking this question.
I hear a lot about benefits of running in the zone 2. Right now I'm reading an article discouraging being in zone 3 for light runs (or hard ones - this is what zone 4 is for).
The question is: what if I'm not capable of running in zone 2 AT ALL? Everything that qualifies as running gets me into zone 3 after ~ 5 minutes, and to get out of it I need to start walking (very quickly dropping into zone 1).